Within the SCT user interface (UI) export the shapefile templates from SCT user interface for use in GIS platform (ESRI or QGIS). These shapefile templates consist of a study area polygon, hazard source interface polyline (HSIP), and a planning reach polygon. The purpose of each template is described in the following sections. Instructions for generation of SCT polygons and polylines can be found in “CHART SCT Detailed Workflows” document located (link).

Study Area Boundary Polygon

The purpose of the Study Area Boundary shapefile template is to set the location, zoom extents and boundary conditions for the study. The study area boundary should allow the study team to remove areas that are not pertinent to the analysis but be large enough to reasonably describe all relevant impacts. Information that could be associated with the study area boundary includes the study name, authority, need, location and background information.

< Instructions generated with ArcPro 3.1.0 >

Study Area Shapefile workflow using ESRI

In the Catalog Pane, choose a location where the shapefile will be saved.
Right click the folder location and select “Feature Class” in the “New” section.
Enter a name/alias for the shapefile and select polygon for the Feature Class Type.
On page 3/6 of Create Feature Class, ensure that the spatial reference is set to WGS 1984 Web Mercator (auxiliary sphere).
Select “Finish” to generate the new feature class.
Under the Edit menu, select create in the “Features” section.
The new feature class will be listed in the Create Features Pane, select the polygon tool in the pane.
Create the desired boundaries for the shapefile using the polygon tool.
To save the shapefile, right click the feature in the Contents Pane and select “Export Features” under “Data”.
Select the folder location to save the shapefile to and a name for the shapefile before saving.

Upload Shapefile to CHART

Navigate to the folder containing the shapefile.
Select the following files: *.cpg, *.dbf, *.prj, *.shp, *.shx.
Right click and select Send to -> Compressed (zipped) folder.
Either drag and drop or browse to and select the zipped folder in the CHART interface.

Hazard Source Interface Polyline

Hazard Source Interface Polyline (HSIP) shapefile template serves the following purposes for the SCT:

It serves as a visual delineation of the location and length of the shoreline area that is the primary source of the risk.
It is associated with the floodplain analysis in terms of understanding where the flood starts and how it spreads.
It should encapsulate the hazard and physical setting components of the coastal storm risk.
It provides the user with information with respect to the potential siting of CSRM measures.

The HSIP should for the most part trace the shoreline, capture the controlling elevations that prevent flood hazards, and represent the coastal floodwater, erosion, or wave attack source. Care should be taken with citing the HSI especially if used for parametric benefit to cost comparisons.

Instructions for HSI generation can be found in “CHART SCT Detailed Workflows” document located (link).

[Structural plans are likely cited along an HSI, while nonstructural measures are not necessarily tied to an HSI]

Planning Reach Polygon

Planning reach polygons are containers for the coastal storm risk characterization for the study. Their development is influenced by geopolitical boundaries, hazard characterization, exposure levels, protection type, and risk mitigation alternative considerations. In addition to encapsulating the HSIP, they also contain all exposure and vulnerability information. Within the SCT, the planning reach serves as the primary level of decision making for scoping purposes. As such the following are described at the planning reach level:

All risk, problem, and opportunity statements
Planning objectives and constraints
Alternatives, measures, and measure cost ranges.

Exposed populations, property, and critical infrastructure are all planning reach level risk components. Note that any alternative that will protect multiple planning reach polygons requires an overall evaluation of the polygons included. Development of Planning Reach Polygons is detailed in the “CHART SCT Detailed Workflows” document located (link), following the same procedure as the Study Area Boundary Polygon.